Generally, the recoil mechanisms of some large caliber weapons systems employ a recuperator assembly including a cylinder having a floating piston separating the hydraulic fluid from a gas fluid. The position of the floating piston is usually monitored as an indicator to determine if an adequate volume of hydraulic fluid or gas exists in the cylinder to assure proper recoil operations of the weapon system.
In the past one method utilized to monitor the position of the piston has been to attach a rod to the piston which rod slidably extended at its other end through a seal in the cylinder whereby the external portion of the rod could be used to indicate the position of the piston in the cylinder. In weapon recoil systems the rod extended through the liquid side of the cylinder in the recuperator assembly because greater difficulties would be encountered in sealing of the gas side of the cylinder. The sealing requirements of the rod tended to lower the reliability of the hydraulic system. Even with this arrangement, sealing of the liquid side presented additional problems because of the high pressures involved in operation of the recuperator assembly. This rod approach presented further problems in that light-weight rods would tend to break and the rearward high speed travel of the rod could endanger crew (in one case the cylinder is approximately 80 inches long). The rod approach also required precision machined parts adding considerably to cost.
By utilizing the present invention these problems and difficulties, among others, of the prior art are substantially overcome by the provision of means for visually monitoring the position of the floating piston in the cylinder by connecting spring coil means to one end of the piston and mounting the other end of the spring coil means in the transparent gas side of the cylinder interior in a location where there is a high pressure resistant window through which the operator may view with minimum distortion the inside of the cylinder and read out sections of the spring means on which are marked indicia indicative of the position of the floating piston to determine whether the volume pressures in the cylinder are adequate.
Accordingly, it is an object of the present invention to provide new and improved means for visually monitoring the position of a floating piston in a cylinder to determine whether adequate fluid volume exists in the cylinder without removing the parts of the cylinder.
Another object of the present invention is to eliminate the necessity of utilizing a rigid rod carried by the piston which extends through the end of the cylinder and which carries readout indicia for indicating the position of said piston.
Still another object of the present invention is to eliminate the safety hazards attendant use of the rod indicating approach.
A further object of this invention is to eliminate the sealing requirements of the extending rod approach.
A still further object of the invention is to increase the reliability of high pressure cylinder assemblies, such as found in the recuperator assemblies of recoil mechanisms of large caliber weapons systems.